1. Casting method: This is a traditional processing method. It requires a complete set of smelting, pouring and other equipment. It also requires a larger plant and more workers. It requires large investment, many processes, complex production processes, and pollution. The environment and the skill level of the workers in each process directly affect the quality of the product. The problem of leakage of the pores of the stainless steel spheres cannot be completely solved. However, the blank processing allowance is large and the waste is large, and it is often found that the casting defects make it scrapped during the processing. , As the product cost increases and the quality cannot be guaranteed, this method is not suitable for our factory.
2. Forging method: This is another method used by many domestic valve companies. It has two processing methods: one is to cut and heat forge into a spherical solid blank with round steel, and then perform mechanical processing. The second is to mold the circular stainless steel plate on a large press to obtain a hollow hemispherical blank, which is then welded into a spherical blank for mechanical processing. This method has a higher material utilization rate, but a high-powered The press, heating furnace and argon welding equipment are estimated to require an investment of 3 million yuan to form productivity. This method is not suitable for our factory.
3. Spinning method: The metal spinning method is an advanced processing method with less and no chips. It is a new branch of pressure processing. It combines the characteristics of forging, extrusion, rolling and rolling, and has high material utilization ( Up to 80-90%), saving a lot of processing time (1-5 minutes forming), the material strength can be doubled after spinning. Due to the small area contact between the rotating wheel and the workpiece during spinning, the metal material is in a two-way or three-way compressive stress state, which is easy to deform. Under a small power, a higher unit contact stress (up to 2535Mpa) Therefore, the equipment is light in weight and the total power required is small (less than 1/5 to 1/4 of the press). It is now recognized by the foreign valve industry as an energy-saving spherical processing technology program, and it is also suitable for processing Other hollow rotating parts. Spinning technology has been widely used and developed at a high speed abroad. The technology and equipment are very mature and stable, and the automatic control of the integration of mechanical, electrical and hydraulic is realized. At present, spinning technology has also been greatly developed in my country and has entered the stage of popularization and practicality.